1. I wrote humorous content for the Heroes section on the portal, http://www.heroesportal.net/tavern/?id=252699&pagenum=8
2. The agreement would be something like, "I'm okay with 4000+500, if you're not, state your defeat."
I came to this conclusion because once, the organizer of a tournament decided that 4 minutes wasn't enough for the SOD (Single-Opponent Duel), and they needed to introduce 6 minutes for the Portal tournament. I got Rebellius in the tournament. I said, "We play for 4 minutes, or you advance without a fight." Rebellius decided it was easier to advance without a fight.
P.S. The Portal rules stated 4 minutes.

Let me explain in a way that won't offend you. You see, your desire to play with limits of 1800+300, 4 minutes, etc., would be taken more seriously if you demonstrated a high level of play, and (in my opinion) you don't. I don't remember which timer we used for our chaotic game, but I know it was shorter than the standard one. Based on the replays I've seen, I have a strong impression that you don't use much time in your games not because you manage to do everything, but because you don't know what else you could have done. This doesn't refer to drawn-out battles with machine guns or, say, 2 Psychos against a horde of zombies.
As for games where maneuvering begins instead of just rushing, where you clear the path, fight, and shake hands – in those games, you definitely need at least 400 more points. Just now, I agreed to a draw with Dobber in an ORP (One-Round Play) game – the time was 225, the timer was 400+400, I was close to zero, and he was close to that as well. We both used 4-5 heroes at the end, even though we were using quick play throughout. There simply wasn't enough time for more.